直立独龙蔓不同高度结果部位对葡萄酒香气物质成分的影响

以宁夏玉泉营农场直立独龙蔓整形方式下酿酒葡萄梅鹿辄、赤霞珠和霞多丽为试验材料,研究不同高度结果部位对葡萄酒香气物质成分及含量的影响。结果表明,梅鹿辄、赤霞珠、霞多丽三个供试品种不同结果部位葡萄酒中香气物质总量均表现为上层结果区＞中层结果区＞下层结果区,其中主要香气物质酯类和醇类的相对含量占比均为上层结果区＞中层结果区＞下层结果区。通过对香气成分进行主成分分析,初步确定了各品种不同高度结果部位葡萄酒特征性香气成分。建议改变宁夏产区整形方式,使结果部位保持在同一高度,以获得香气物质含量一致的优质葡萄酒。     

由多酚物质剖析葡萄酒的差异性

不同的葡萄酒都有其特征性,这取决于葡萄品种、生长环境、酿酒工艺等因素.但即使在相同葡萄品种、生长在同一区域、相同工艺条件情况下,不同产地的葡萄酒仍存在着某些差异.以烟台地区蛇龙珠葡萄为例,剖析葡萄酒中多酚物质的微小变化.结果表明,多酚物质是葡萄酒存在差异性的主要原因之一.     

基于葡萄酒多酚物质水平的葡萄酒鉴别

该文以4个主要葡萄酒产区（宁夏、烟台、甘肃和新疆）、3个酿酒葡萄品种（小味儿多、赤霞珠和马瑟兰）的葡萄酒样品为原料,利用超高效液相色谱-三重四极杆串联质谱技术,分析葡萄酒中37种多酚物质的含量,结合多元统计分析,探讨葡萄酒品种鉴别和产地溯源的可行性。结果表明,不同品种和不同产区葡萄酒中分别有22种和28种多酚化合物含量存在显著差异;经过主成分分析,在不同品种葡萄酒中筛选出咖啡酸、对香豆酸、阿魏酸和花旗松素等16种特征多酚化合物,在不同产区葡萄酒中共筛选出柚皮素、杨梅素、香草酸和根皮素等15种特征多酚化合物;通过Fisher判别分析,不同品种葡萄酒回代检验和交叉检验的整体正确判别率分别为100.0%和91.9%,不同产区葡萄酒回代检验和交叉检验的整体正确判别率分别为100.0%和97.4%。说明基于多酚类化合物指纹的差异可以有效鉴别不同品种和不同产区的葡萄酒。     

主成分分析法研究酚类物质对葡萄酒品质的影响

利用主成分分析法研究了葡萄酒中酚类物质对葡萄酒品质的影响.结果表明,几茶素、没食子酸、绿原酸和芦丁对葡萄酒品质影响最大.儿茶素、没食子酸的影响是正面的,芦丁和绿原酸的影响是负面的.     

不同产区葡萄酒多酚物质抗氧化活性差异及相关性分析

以西北部产区(焉耆盆地、吐哈盆地、天山北麓、伊犁河谷)及中部产区(河北产区)葡萄酒为样本,测定其多酚组成及抗氧化能力,分析样品间差异性及相关性,探究影响抗氧化功效的单体酚物质.通过对酚类物质含量、DPPH、ABTS+、羟自由基清除率的测定,结果显示,西北部产区样品酚类物质含量高,且种类丰度较高;焉耆与伊犁产区葡萄酒抗氧...     

后处理工艺对红葡萄酒多酚物质和色度的影响

研究了后处理工艺对葡萄酒色度和多酚物质含量的影响,为合理制定工艺提供依据.实验表明,下胶、冷冻和膜过滤等后处理工艺都不同程度的降低了葡萄酒的色度和总酚含量,降低了葡萄酒的外观颜色和品质,其中大的下胶量和长时间冷冻处理对葡萄酒的色度和总酚含量影响最大,最大下降比率分别为16.0％、6.7％和14.7％、14.2％,而从勾兑到灌装,所有处理使色度和总酚累计下降25.3％、18.8％;对如何降低后处理工艺对葡萄酒色度和多酚的影响,提出了可行性建议.     

花生蔓不同部位黄酮含量的研究

花生蔓中含有丰富的黄酮类化合物,采用分光光度法,以芦丁为标准品,测定花生蔓中不同部位总黄酮含量.通过L9(34)正交试验设计,考察了提取条件与黄酮提取量的关系.结果表明,花生蔓中黄酮类物质的最佳提取工艺为:乙醇浓度60%,提取温度65℃,料液比1g∶40ml,超声时间20min.     

葡萄酒中多酚物质抗氧化活性测定方法的研究

对葡萄酒中酚类物质抗氧化活性检测方法的研究状况进行概述,重点阐述了体外非酶法测定抗氧化活性的几类方法,比较了它们的优缺点;分析了国内外抗氧化测定方法的使用现状,并展望了抗氧化活性的测定方法。     

牡丹不同部位多酚含量研究

本研究以牡丹根、茎、叶、花为原料,用乙醇作为浸提剂,对牡丹多酚提取沉淀时铝用量及pH值进行了研究。以正交试验研究了多酚沉淀转溶的工艺参数,对牡丹根、茎、叶、花中多酚含量进行了分析。结果表明,AlCl3法沉淀牡丹多酚的条件为:0.1mol/LAlCl3溶液用量2.5ml,pH5.3。牡丹多酚沉淀的最佳条件为:硫酸浓度1mol/L,料酸比1:1(V/V),温度55℃,时间5min。牡丹各部位多酚含量从高到低分别为:根、叶、茎、花。     

基于多酚含量的赤霞珠葡萄酒年份鉴别研究

对比分析贺兰山东麓同一酒庄不同年份赤霞珠单品葡萄酒中多酚含量差异,基于此探讨酚酸、黄酮醇、黄烷醇代谢产物在葡萄酒年份鉴别中的可行性。采集贺兰山东麓永宁产区同一酒庄2018—2023年这6个年份的葡萄酒样品共计18份,监测分析葡萄酒中酚酸、黄烷醇、黄酮醇含量差异,采用Fisher线性判别分析方法,构建基于酚酸、黄烷醇、黄酮醇指标的葡萄酒年份鉴别模型。结果显示,赤霞珠单品葡萄酒中的21种酚酸、6种黄烷醇、10种黄酮醇在不同年份间均存在显著差异,新酒中黄烷醇、羟基肉桂酸含量低于老酒,黄烷醇高于老酒;采用Fisher线性判别分析方法,分别基于酚酸、黄烷醇、黄酮醇指标构建葡萄酒年份鉴别模型,正确鉴别率均达到94.4%以上。研究结果表明,基于葡萄酒中酚酸、黄烷醇、黄酮醇任意一种成分均可实现同一产地不同年份葡萄酒的准确鉴别。     

Effect of polyphenols on the perception of key aroma compounds from Sauvignon Blanc wine

Background and Aims:  Sensory wine research has mainly focused on the role of volatile compounds and their contribution to the aroma profile. Wines also contain polyphenolic compounds, which are not volatile. This research begins to investigate the interactions of volatile and non-volatile wine compounds and the consequential effects on sensory perception of aroma.
Methods and Results:  Trained panellists of this study measured the perception of four aroma compounds (isobutyl methoxypyrazine, 3-mercaptohexanol, 3-mercaptohexanol acetate and ethyl decanoate) in wine. Panellists assessed the four compounds in combinations with three polyphenols (catechin, caffeic acid and quercetin) commonly found in white wine. The perception of isobutyl methoxypyrazine, 3-mercaptohexanol and ethyl decanoate was largely suppressed by the added polyphenols, while the perception of 3-mercaptohexanol was accentuated with the addition of caffeic acid. Of the three polyphenols, only catechin had a slight effect of accentuating the mercaptohexanol acetate perception.
Conclusions:  Results showed each polyphenol had a unique effect when blended with a specific aroma compound, either suppressing, accentuating or showing little effect on the perception of the aroma compounds.
Significance of the Study:  Understanding these interactions can assist winemakers in managing polyphenol levels to optimize selected volatile compounds to achieve desirable aroma profiles.     

葡萄含糖量对蛇龙珠葡萄酒品质的影响

选取蛇龙珠葡萄为研究对象,对葡萄初始含糖量与蛇龙珠葡萄酒品质的关系进行研究.结果表明,随着初始含糖量的增加,葡萄酒中的总酚含量呈上升趋势,这有利于增加红葡萄酒的色泽及感官质量.初始含糖量增加,多数醇类和酯类成分的检出量也有所增加,主要包括2-甲基-1-丙醇、3-甲基-1-丁醇、2-甲基-1-丁醇、2,3-丁二醇、乙酸乙酯和丁二酸单乙酯.上述醇类和酯类均具有各自独特的感官特征,其含量的适量增加有利于提升葡萄酒的口感质量.葡萄原料糖分含量高时,葡萄酒口感圆润、醇厚,酒体丰满,结构感也比较强.综上所述,葡萄初始含糖量对葡萄酒品质具有极其重要的影响.酿造优质蛇龙珠干红葡萄酒时,应选择初始含糖量高的葡萄原料.     

Effect of storage on the phenolic content,volatile composition and colour of white wines from the varieties Zalema and Colombard

Different quality attributes and chemical components of wines change during storage as a function of a series of factors. Thus, in young white wines, changes in phenolics, that lead to modifications of their colour as a result of oxidation processes, are well-known. These reactions can also alter their volatile profile giving rise to the appearance of new aromas, which in some cases are undesirable. In this study we have carried out a thorough evaluation of the changes in the colour, volatiles and phenolics of Zalema and Colombard wines during 1 year of storage under different conditions of temperature and position. The phenolics and colour were more affected than was the volatiles profile and wines kept in the cold could be clearly distinguished from the others, whilst the position of the bottles onlt slightly affected the wines during storage. Results showed that the blending of Zalema wines with Colombard wines may be an appropriate means of enhancing the acidity of the former without dramatically affecting its character.     

Copper content of grape and wine from Italian farms

The copper content of grape and wine from 16 wine-farms in Italy was studied during the harvest of 2003. The influence of the number of copper applications, the period between the last application and harvest, and the total amount of copper applied was examined. Of the total number of samples analysed, 13% of grape samples and 18% of wine samples exceeded the maximum residue level (MRL). The total amount of copper applied and the number of days between the last application and harvest explained 44% of the concentration of copper in grape. This low correlation may be due to other influencing factors, such as meteorology and the application method. In 2003, conditions were unusually dry and the recommended safety interval for copper application (20 days) was not sufficient to guarantee a residue level in grape below the MRL (20 mg kg^-1). In order to reduce the probability of copper residues being close to the MRL, a period of 40-50 days between the last application and harvest is suggested. Furthermore, the copper content of grape and wine was not dependent on the pest management strategy of the farm (conventional, integrated or organic). A more important factor influencing copper residue levels may be that copper applications are made in response to the prediction of a disease outbreak rather than being dependent on the pest management strategy in place. No difference in copper content was observed between red and white grape or wine.     

避雨栽培对赤霞珠葡萄酒非花色苷酚类的影响

研究避雨栽培对葡萄酒非花色苷酚类的影响,为酿酒葡萄避雨栽培技术的实施提供理论依据。采取简单避雨方式,以赤霞珠(Vitis vinifera L cv.Cabernet Sauvignon)葡萄为材料,在转色后进行避雨处理,以露地栽培为对照;葡萄收获后采用传统工艺酿制干红葡萄酒,测定其基本理化指标及非花色苷酚的种类和含量,获得如下结果:(1)避雨栽培降低了赤霞珠葡萄酒总酸、总酚和单宁含量,但差异不显著。(2)避雨栽培对一些单体非花色苷酚类含量存在显著影响,显著降低了黄烷醇类总量,但对黄酮醇和类黄酮酚总量无显著影响;极显著降低了苯甲酸、芪类和非类黄酮酚,增加了肉桂酸类含量。(3)对葡萄酒非花色苷酚类物质种类无影响,降低了非花色苷酚类总量但差异不显著。因此,在赤霞珠葡萄转色期采取避雨措施,对干红葡萄酒非花色苷酚类的影响不显著。     

枸杞酒酿造过程中的酚酸降解规律

枸杞酒发酵过程中酵母代谢产生一些有机酸、醇、醛、酮等复杂的物质,使发酵环境发生了变化,迫使酚酸物质在此环境下发生氧化、还原或与环境中的物质发生化学反应从而产生各种降解产物.实验测定了酚酸物质在发酵过程中含量的变化及降解产物,并通过模拟实验,验证枸杞发酵时可能产生的降解产物.结果表明,从实验所用枸杞中共检测出7种酚酸单体...     

Evolution of the phenolic content of red wines from Vitis vinifera L. during ageing in bottle

The evolution of the phenolic content, as measured by spectrophotometric methodologies [total polyphenols (TP), low-polymerized polyphenols (LPP), total anthocyanins (TA), catechins (CAT), proanthocyanidins (PRO) and o-diphenols (OD)], was studied in young red wines from Vitis vinifera L. cv Tempranillo, Graciano and Cabernet Sauvignon during 26 months of ageing in bottle. Although the wines showed differences in their initial phenolic profiles, the evolution trend of the different families of phenolic compounds was similar in the wines from the three grape varieties. TA markedly decreased during ageing in bottle (43% for Tempranillo, 65% for Graciano and 66% for Cabernet Sauvignon), following a first-order kinetic. Calculation of the kinetic parameters revealed that the disappearance rate of TA was 2-fold lower for Tempranillo wine than for Graciano and Cabernet Sauvignon wines, which exhibited similar kinetics. This decrease in TA (due to the disappearance of monomeric anthocyanins), together with a increase registered in CAT and PRO (due to the cleavage of proanthocyanidins and their structural tranformations), was consistent with a decrease in LPP, suggesting the occurrence of condensation reactions during ageing in bottle. The evolution trends observed for TP and OD during ageing in bottle were the results of changes in the different groups of phenolic compounds involved in both determinations. Global phenolic determinations, usually performed in wineries, provided useful information in relation to the evolution of wine polyphenols during ageing in bottle.     

Measurement of total phenolic content in wine using an automatic Folin–Ciocalteu assay method

Measuring the total phenolic content in wine is important in estimating the taste and health benefits of wine. We developed an automatic Folin–Ciocalteu (F‐C) method to reduce processing times (3 min), human errors and waste volume as compared it to the manual method. The gallic acid standard responded linearly up to 5000 μg mL^?1, and the wine dilution series responded linearly between four‐ and sixteenfold dilutions. Anthocyanins showed slower reaction rate compared with wine, gallic acid and quercetin, while ascorbic acid showed the fastest rate. Fructose and glucose at the 10% level showed approximately 8% interference in port wines, and the interference was thought to be negligible in most dry wines containing <1% sugar. Total phenolic contents ranged between 1600 and 3300 μg mL^?1 by the automatic method and were approximately 20% less than those by the manual method, except in pink wines which was nearly identical. The regression analysis of the phenolic contents showed a very linear relationship between the methods (r² = 0.97***). This automatic method was thought to be efficiently adopted in wine testing laboratories as a fast and reproducible assay.     

Original article: Prediction of the colour and polyphenolic composition of the young red wines from the phenolic potential of the grapes

The phenolic potential of the grapes of Tannat, Cabernet Sauvignon and Merlot produced in the south region of Uruguay was analysed in four years. The grapes of Tannat had the highest total phenolic richness (A280 = 80.0), total anthocyanin potential (ApH1 = 2540 mg L^?1) and extractable anthocyanin potential (ApH3.2 = 1269 mg L^?1), although there were important differences between the years. Representative winemaking of each vineyard was carried out. The differences verified in the grapes phenolic indexes were related to the colour and polyphenolic composition of the wines. The correlations between the phenolic indexes of the grapes and the colour and polyphenolic composition of the wines were very high. The estimation of the polyphenolic richness and the extractability of the anthocyanins of the grapes allow to improve the management of the winemaking and the prediction of the chromatic characteristics and the global polyphenolic composition of the wines.     

Influence of the heterogeneity of grape phenolic maturity on wine composition and quality

Nowadays, consumers demand red wines with deep colour, soft tannins and fruit scents, but these wines can only be obtained from grapes with complete phenolic maturity. Diverse methods have been proposed for measuring phenolic maturity. However, all these methods only provide the average value and do not consider any possible heterogeneity. Throughout ripening, grapes were separated according to their density, which revealed the existence of a large heterogeneity. Grapes at harvest were also separated by density in three groups. The higher the density of the grapes the higher ethanol content, pH, colour intensity, total phenolic index and anthocyanin and proanthocyanidin concentrations, and the lower the titratable acidity and bitterness of the wines. When the grapes were denser the wines were also better balanced in flavour and mouthfeel sensation. These results suggest that grape heterogeneity may influence the final wine composition and quality and therefore it should be considered at harvest.